<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title></title>
<script type="text/javascript">
function SetValues()
{
    var s =  + window.event.clientX +  ' ,' + window.event.clientY ;
	console.log(s);
	var canvas = document.createElement("canvas");
	canvas.setAttribute("width", window.innerWidth);
	canvas.setAttribute("height", window.innerHeight);
	canvas.setAttribute("style", "position: absolute; x:0; y:0;");
	document.body.appendChild(canvas);
	var ctx = canvas.getContext('2d');
	ctx.fillRect(window.event.clientX,window.event.clientY,3,3); 
	
}  

</script></head>
<body onclick=SetValues()>

</body></html>